Importance of clinical staging in limited small-cell lung cancer: a valuable system to separate prognostic subgroups. The University of Toronto Lung Oncology Group.

PURPOSE: In an attempt to assess the response to treatment and survival of a group of patients treated with standard chemotherapy and radiotherapy, we undertook a retrospective review of small-cell lung cancer (SCLC) patients treated by the University of Toronto Lung Oncology Group. PATIENTS AND METHODS: We reviewed the records of 264 patients with limited SCLC who were treated from 1976 to 1985. Based on radiologic review and physical examination, patients were assigned to three prognostic groups: group 1 (very limited SCLC), negative mediastinoscopy and/or no evidence of mediastinal nodes on radiologic review; group 2, x-ray evidence of mediastinal node involvement or a positive mediastinoscopy; group 3, supraclavicular adenopathy or x-ray evidence of pneumonic consolidation, pleural effusion, or atelectasis. All patients received combination chemotherapy, radiotherapy to the primary site, and prophylactic cranial irradiation. RESULTS: Complete response was seen in 52% of patients and partial response in 29%. Response rates did not differ among the three prognostic subgroups. The median survival time for patients in group 1 was 15.7 months, compared with 12 months for group 2 and 11 months for group 3 (P = .0175). Projected 5-year survival for group 1 was 18%, compared with only 6% and 2% for groups 2 and 3, respectively. There was no difference among the prognostic subgroups with respect to either local or distant recurrence rates. CONCLUSION: Using simple clinical staging techniques, we were able to identify a subgroup of patients with very limited SCLC who had a significantly better prognosis. We recommend that randomized clinical trials stratify patients according to the presence or absence of clinically detectable mediastinal lymphadenopathy.